Open cell tray and method of foodstuff packaging

ABSTRACT

A packaging system includes a packaging member adapted to support a foodstuff in use. The packaging member comprises a container or tray formed from an open celled material. The container or tray has an inside intended to contact the foodstuff in use and an outside.

FIELD

[0001] The present invention relates to packaging and is particularly, but not exclusively, relates to the packaging of foodstuffs, including meat products.

BACKGROUND

[0002] One of the aims when packaging foodstuffs, especially fresh meat products and the like, is to remove as much oxygen from the package as possible; in fact ideally, to provide an oxygen-free environment therein. Oxygen allowed to remain in contact with the foodstuff can result in the foodstuff deteriorating as it provides an environment in which undesirable micro-organisms may proliferate. Systems are known which help address this issue. Such systems often involve the evacuation of air from the package and the subsequent charging of the package with an inert atmosphere gas such as carbon dioxide. The carbon dioxide acts as a bacteriostat. A problem with such systems is that there may be a residual amount of oxygen left in the cells of the packaging materials themselves (eg polystyrene foamed plastic trays).

OBJECT

[0003] It is an object of the present invention to provide packaging or a packaging system which will obviate or minimise the foregoing disadvantages in a simple yet effective manner or which will at least provide the public with a useful choice.

STATEMENT OF INVENTION

[0004] Accordingly in one broad aspect of the present invention there is provided a packaging system including a packaging member adapted to support a foodstuff in use, the packaging member comprising a container or tray formed from an open celled material, the container or tray having an inside intended to contact the foodstuff in use and an outside.

[0005] Preferably the outside has a layer of material over at least a substantial portion of the area thereof, the layer of material being substantially solid.

[0006] If desired the packaging member has a further solid layer over at least a substantial portion of the inner surface.

[0007] Preferably the packing system further includes a gas permeable membrane adapted to co-operate with the packaging member to substantially enclose the foodstuff within the packaging member in use.

[0008] Preferably, the packaging system further includes a pouch or outer barrier bag adapted to receive one or more wrapped packaging members in use, the pouch being constructed of a material substantially impermeable to gases in use and being adapted to be sealed in use to form an inert atmosphere gaseous environment within said pouch.

[0009] In another broad aspect of the present invention there is provided a packaging member adapted to support a foodstuff in use, the packaging member being formed from an open celled material.

[0010] Preferably the packaging member has a layer of solid material on at least a substantial portion of the outer surface thereof.

[0011] If desired the packaging member has a further solid layer over at least a substantial proportion of the inner surface.

[0012] In another broad aspect of the present invention there is provided a method of:

[0013] placing the foodstuff in a packaging member comprising a container or tray formed from an open-celled material;

[0014] overwrapping the packaging member with a layer of material having micro-perforations in it;

[0015] placing at least one packaging member within a pouch or outer barrier bag;

[0016] evacuating the normal atmosphere from the pouch or outer bag;

[0017] charging the pouch or outer barrier bag with an inert gas atmosphere

[0018] Preferably the machinery used to evacuate the normal atmosphere is a SECUREPAK™ machine.

[0019] The invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features, and where specific integers are mentioned herein which has known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

PREFERRED EMBODIMENT

[0020] One embodiment of the present invention will now be described with reference to the accompanying drawing in which FIG. 1 is a diagrammatic cross-section of a packaging member.

[0021] The following is a description of the preferred embodiments of the invention, given by way of example only. It will be appreciated that a variety of changes and modifications may be made to these examples, and a range of other embodiments are possible, within the general scope of the invention.

[0022] The present invention relates to containers or receptacles for foodstuffs to be packaged, and related packaging systems, and may be incorporated into any standard foodstuff packaging method being compatible with standard known foodstuff, packaging apparatus and machinery. In addition, the invention may be used in the packaging of a variety of different foodstuffs including meat and cheeses for example.

[0023] Within this specification the word “package” is used to describe the packaging, which may be comprised of a number of separate components which interact in use, which substantially surrounds the foodstuff in use. For example, a tray on which foodstuff is supported which has been overwrapped with a suitable membrane may be referred to as a package. Alternatively, the pouch which may contain a number of individually wrapped trays having foodstuff thereon may also be considered a package. Those of general skill in the art will realise other examples of packages which fall within the scope of the present invention.

[0024] In FIG. 1 a packaging member is provided which may be in the form of a tray 1 of the kind commonly used to pack and display meat and the like; having a base 2 on which the foodstuff to be packed is supported in use and a lip 3 projecting at an angle therefrom around the perimeter of the base 2 which acts to help contain the product. Thus the tray 1 described is in the form of a shallow dish. The tray 1 is constructed of material commonly used in the foodstuffs industry; for example, a plastics material compatible with the packing of foodstuffs. The tray is constructed substantially of a layer 5 of an open cell plastic material with a thin layer of solid material 6 on an underside thereof. The open celled construction on the surface of the tray 1 supporting the foodstuff allows liquid to be absorbed into the tray and the thin layer of solid material 6 on the underside of the tray 1 acts to retain the liquid therein. The outer solid layer 6 may be about 100 microns to about 200 microns thick. The inner solid layer 7 must allow oxygen evacuation therethrough, and, for example, may be from about 15 microns thick to 30 microns thick. The principal purpose of this layer is to stiffen the construction.

[0025] The layer 5 of the open celled material is preferably open celled polystyrene. The layers of solid material may be styrene.

[0026] In use, the foodstuff, fresh meat for example, will be placed on the tray and the tray then overwrapped with a web of covering or wrapping membrane 4. It will be appreciated that the covering is generally made of a clear plastic material but may be made of any other suitable material. In this preferred form of the invention the covering is perforated, preferably micro-perforated, to ensure gas equilibration between enclosed regions of the overwrapped tray and the outside ambient atmosphere. One tray, or a number of similarly wrapped trays, may then be placed within a pouch or outer barrier bag (not shown) which is evacuated of normal atmosphere, which contains 20.9% oxygen to an atmosphere containing 300 ppm oxygen or less. This evacuation is used by a SECUREPAK™ machine, and then charged with carbon dioxide or other inert atmosphere gas capable of substantially preserving the foodstuff (nitrogen, or suitable mixtures, for example). The pouch is then sealed and the packaged foodstuff may be stored at an appropriate temperature and/or transported for sale. Oxygen in the open celled layer 5 will be substantially removed during the evacuation process.

[0027] The rate of evacuation of air and charging with carbon dioxide or other suitable inert atmosphere gas may be altered according to the packaging system being employed, the size of the package and the like.

[0028] It will be appreciated that, if desired, the material from which the pouch or outer barrier bag is made may contain an oxygen absorbent material. For example, the material must have minimal oxygen permeability; foil laminates, metallised films and high barrier plastic films. In addition, the sealing of the pouch must be effective so as to ensure a stable gaseous environment within the package and in particular to ensure the invasion of oxygen is inhibited. Alternatively standard methods may be used, for example, placing an oxygen absorbent sachet in the pouch or outer barrier bag.

[0029] It will be appreciated by those of general skill in the art that following storage and transportation of meat packaged according to the present invention the pouch may be opened with a resultant bloom time of 20 to 30 minutes.

[0030] The present invention may have the advantage of helping to increase the shelf life of packed meat. For example, under ideal conditions (held at approximately −1.5° C.) fresh lamb may be stored for twenty weeks with no adverse affects on the meat. Similarly, it may be displayed chilled in a store environment for four days. 

What we claim is:
 1. A packaging system including a packaging member adapted to support a foodstuff in use, the packaging member comprising a container or tray formed from an open celled material, the container or tray having an inside intended to contact the foodstuff in use and an outside.
 2. A packaging system of claim 1 wherein the packaging member is overwrapped with a layer of material having a micro-perforations in it.
 3. A packaging system of claim 2 wherein at least one packaging member is placed within a pouch or outer barrier bag which is then evacuated of normal atmosphere and then charged with an inert atmosphere gas.
 4. A packaging system of claim 3 wherein the material from which the pouch or outer barrier bag is made contains an oxygen absorbent material.
 5. A packaging system of claim 3 wherein an oxygen absorbent sachet is placed within the pouch or outer barrier bag.
 6. A packaging member adapted to support a foodstuff in use, the packaging member being formed from an open celled material.
 7. A method of packaging foodstuffs comprising steps of: placing the foodstuff in a packaging member comprising a container or tray formed from an open-celled material; overwrapping the packaging member with a layer of material having micro-perforations in it; placing at least one packaging member within a pouch or outer barrier bag; evacuating the normal atmosphere from the pouch or outer bag; charging the pouch or outer barrier bag with an inert gas atmosphere.
 8. The method of packaging foodstuffs as claimed in claim 7 wherein the material from which the pouch or outer barrier bag is made contains an oxygen absorbent material.
 9. The method of packaging foodstuffs as claimed in claim 7 wherein an oxygen absorbent sachet is placed within the pouch of an outer bag.
 10. The method of packaging foodstuffs as claimed in any one of claims 7, 8 or 9, wherein a SECUREPAK™ machine is used to evacuate the normal atmosphere. 